Change default languages in front and not in virtuemart backend

[AleCat83]

Hello guys,
I've buit a joomla 2.5 and virtuemart 2  multilanguages website, in italian and english.
Some day ago I've tried to change the joomla defautl languages from italian to english. In the front end I've got no problem, but when I visit virtuemart backend the product list appear in english and I can't see the italian original translation. My goal is to set frontend languages default to english but keep the administrator virtuemart section in italian (setting in joomla are already to front-end ->english, backend->italian).
Thank you and sorry my bad english


Ale